Multiple supply, balanced valve, pressure reducing valves, and the like



p 1966 T. A. BANNING, JR ,7

MULTIPLE SUPPLY, BALANCED VALVE, PRESSURE REDUCING VALVES, AND THE LIKEOriginal Filed Feb. 5, 1956 s Sheets-Sheet 1.

Invenror; 7 Thomas A.Bonning.Jr.

Sept. 6, 1966 T. A. BANNING, JR

MULTIPLE SUPPLY, BALANCED VALVE, PRESSURE REDUCING VALVES, AND THE LIKEOriginal Filed Feb. 5, 1956 Sheets-Sheet 2 InvenTor':

Thomas A.Bcmning,Jr.

BANNING. JR BALANCED VALVE, VALVES, AND THE LIKE Sept. 6, 1966 T. A.3,270.762

MULTIPLE SUPPLY, massums; mwumm;

5 SheeLSSheet .3

Original Filed Feb. 3, 1956 A5 Inve nTor:

ThomosA.Bonning,Jr.

Sept- 1956 T. A. BANNING, JR ,7

MULTIPLE SUPPLY, BALANCED VALVE, PRESSURE REDUCING VALVES, AND THE LIKEOriginal Filed Feb. 5, 1956 5 Sheets-Sheet 1 Helium.

loo

99 Invenror: 137 ThomasA.Bonning,Jr.

Sept. 6, 1966 T A. BANNlNG, JR 3,270,762

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ThomosABunning, Jr.

United States Patent "ice 7 Claims. (Cl. 137-98) This invention relatesto multiple supply, balanced pressure, proportion controlling, reducingvalves, and the like.

This application is a division of my earlier application for LettersPatent of the United States, Serial No. 107,- 948, for Improvements inMultiple Supply, Balanced Valve, Pressure Reducing Valves, and the Like,filed May 5, 1961, allowed March 23, 1965, and which will issue asPatent No. 3,217,730, granted November 16, 1965, which application,Serial No. 107,948 was a division of my earlier application, Serial No.563,306, for Improvements in Life Sustaining Atmospheres, Mixtures ofGases, and Means for producing the Same, and Controlling the Pressuresand Proportions Thereof, filed February 3, 1956, and which becameabandoned after February 27, 1962.

In various operations it is necessary to bring together two or morefluids under conditions such that the proportions of such fluids bear adefinite relation to each other, so that the composition of the mixtureshall be of known proportions. Various means and structures have beenwell known and used widely, for producing such operations; but in caseswhere the fluids comprise gases of fixed nature, the control of theproportioning becomes more difficult, due to the high rate of dispersalof such gases at the instant of bringing them together; and thiscondition is aggravated when the specific gases are of widely differentvalues. The difliculty of producing closely controlled mixtures of theforegoing characteristics is further aggravated when the controlledproportion mixtures are to be produced during or closely related to apressure reducing operation, where conditions of expansion of thecomponents are a further disturbing factor to the production of theexactness of proportion desired in the mixture produced.

A notable example of the difficulties presented in the foregoingstatements resides in the mixing and proportioning of helium and oxygenfor production of controlled proportion mixtures of such ingredients,especially when the produced mixture comprises gases which have justbeen reduced from high pressure sources, such as high compressionflasks, to pressures of the order of 50 to 100 or 200 p.s.i., thepressures in the flasks falling as the contents are delivered, so thatthe degree or extent of the reduction varies greatly over an interval oftime of the operation, while, at the same time the delivered pressure ofthe mixture is also being varied under control. This operation may alsobe further aggravated when the delivery pressure must also be varied,as, for example, during the descent of a diver to deeper amounts ofsubmergence, or conversely, coming up.

The foregoing relationships have been rather fully discussed in myearlier applications, from which the present case is pendant; so thatextended repetition of such operations is not deemed necessary in thiscase. The relationships above mentioned do, however, affect thedesirability of various of the structures and relationships of suchstructures to each other, presently to be disclosed.

3,270,762 Patented Sept. 6, 1966 Certain of the objectives to which thepresent structures are directed include the following:

The delivery openings and passages through which the gases at reducedpressure must travel from the pressure reducing valve elements, arelarge and untrammeled with needless changes of direction, to a controlvalve by which the two gas flows are properly controlled, and arebrought together. Examination of the structures hereinafter to bedescribed, will show that such gas flows for both of the reducedpressure components, are almost by direct lines, with but a singlewidely curved change in direction of the gas flow, to the commonproportion controlling valve, and the mixing chamber to which the gasesare directly delivered by such valve. Such examination will also showthat the proportion controlling valve is so designed and constructedthat there will be a minimum amount of turbulence produced in eachcomponent during its flow through the orifice of its control, and untilthe mixing chamber is entered. Thus the interference with correct andintended proportioning will be affected to a minimum degree during theproportion controlling operation.

A further feature of the invention relates to the form of theproportioning valve itself, in relation to its function of receiving gasfrom the two supply conduits, whereby a single proportioning valveserves both of the gases, providing for them orifices whose openings aresimultaneously varied when change of proportion of the gas rates ismade, according to the intended change in the proportions of the twogases being mixed. This valve includes a mask plate wherein are providedopenings for the two gas flows to the mixing chamber; such openingsbeing of such form that a single movable shield, when moved, increasesthe opening for one of the gases at the same time that the opening forthe other gas is decreased; such increases and decreases being inproportions such that at intermediate stages of the full movement of thevalve, the then exposed sizes of the respective openings will be relatedaccording to the proportions of the mixture desired for such valveposition of movement. In connection with this feature it is a furtherobject to enable change in the various proportions produced bysuccessive amounts of valve movement, to meet specifications imposed bythe particular' use to which the valve is to be placed. In theparticular embodiment hereinafter shown and described, the valve is usedfor controlling the mixture of helium and oxygen, or helium and air,according to the successive hydrostatic pressures existing at successivedepths of water at which a diver may be; and to ensure changes of theratio as the diver descends to deeper and deeper water areas, or risesfrom them; when, in fact it is desired to effect change of such ratiosin order to ensure supply of desired amounts to the diver, of oxygencarried by the mixture of oxygen (or air), and helium or other usableinert gas, other than nitrogen.

In connection with the foregoing object, it is a further object toeffect such change of ratio automatically, during a descent or a raisingoperation, ensuring that at all times the correct ratio between thegases will be supplied to the diver.

Still further, in connection with the foregoing objective it is anobject to properly relate such changing ratio to the delivered pressureof the gases, required according to the water depth of location of thediver. Also, in this connection, to make provision for effecting suchchanges of pressure of the delivered gases, synchronously with changesof the proportions of the two gases, and also according to the descendeddepth which has been attained by the diver, either increasing ordecreasing such depth.

Other objects and uses of the invention are to provide a very simpleform of such control valve, consistent with its intended functions, astructure which can be built of rugged design, consistent with thenature of the operations with which it is intended to be used; and astructure which can be readily assembled or disassembled from time totime, as needed for various purposes.

Also to provide a structure which embodies both of the features of adual pressure reducing valve wherein the delivered pressures of twocomponents are equalized for all adjusted delivery pressures, andwherein the provision is made for delivering the mixture under mixingconditions such that the proportions of the two components may bechanged through a wide range of proportions; combined with structuralmeans whereby, for specified conditions of operation, variations of thedelivered pressure of the mixture shall be accompanied by variations ofthe proportions which the components bear to each other, according to aprescribed formula of these two operative conditions, relative to eachother. The arrangements are also such that such variations of theproportions of the two components with respect to each other,

may be related to the variations of the delivered pressure of themixture under operative conditions imposed by a wide range of theformulas relating these two sets of variations, to each other.

Other objects and uses of the invention will appear from a detaileddescription of the same, which consists in the features of constructionand combinations of parts hereinafter described and claimed.

In the drawings:

FIGURE 1 shows a front elevational view of the assembled dual or duplexpressure reducing valve unit;

FIGURE 2 shows a top plan view corresponding to FIGURE 1, but with theunit rotated 180 degrees in the top plan viewing;

FIGURE 3 shows a left side view corresponding to FIGURE 1;

FIGURE 4 shows a back or delivery end view corresponding to FIGURE 3;

FIGURE 5 shows a bottom plan view corresponding to FIGURE 2, when theunit is rotated 180 degrees about a central horizontal axis parallel tothe top of the unit;

FIGURE 6 shows a cross-section on the lines 66 of FIGS. 1, 2, 4, 5 and7, looking in the directions of the arrows, the parts being set to thelow-pressure delivery position, with the valve ratio controlling valvefully closed against one component (of gas or other fluid), and fullyopened to the other component;

FIGURE 7 shows a plan section on the lines 77 of FIGURES 1, 3, 4, 6 and8, looking in the directions of the arrows; with the ratio controllingvalve in position fully closed against one component, and fully openedto the other component;

FIGURE 8 shows a cross-section on the lines 88 of FIGURES 1, 2, 4, 5 and7, looking in the direction of the arrows; and it shows especially thespring control for controlling the delivery pressures;

'FIGURE 9 shows a fragmentary section taken on the line 9-9 of FIGURE 7,looking in the direction of the arrows; and it shows the control cam;

FIGURE 10 shows a fragmentary section taken on the line 10-10 of FIGURE7, looking in the direction of the arrows; and it shows the rollerholder and the rollers which operate the cam;

FIGURE 11 shows a fragmentary side view of the cam, developed, being adetail view, and being taken on the line 1111 of FIGURE 9, looking inthe direction of the arrows;

FIGURE 12 shows a development of the ports of the valve, showing the twoports of the mask developed into a plane; and one of the ports is shownfully closed by the shading, and the other port is shown fully open bythe lack of shading;

FIGURE 13 shows by means of curves the variation of the ratios of thecomponents of a typical mixture with change of the delivery pressure,the curves being carried backwardly from the sea-level pressure line, toshow that for pressures lower than sea-level percentage of oxygen shouldbe increased in order to ensure the same number of molecules of oxygenper cubic centimeter as are provided in ordinary air at sea-levelpressure; and

FIGURE 14 shows, by means of curves, the variation absorption of theinert gas by the blood stream and bodily tissues, with variations ofpressure, both for nitrogen and for another inert gas; the curves beingtypical, and being related to a danger line.

Referring to FIGURE 13, I have therein shown by means of curves theratios of pressures to percentages for various conditions of use ofmixtures of gases at various pressures and at varying ratios. Pressuresare shown by the abscissae and percentages are shown by the ordinates.These curves show the relationships between such pressures and ratios orpercentages of components of an artificial atmosphere, intended forsupply to and used by a deep-sea diver, or for use under conditionssimilar to such deep-sea diving operations. The sea-level pressure isshown by the line A. The line C shows the oxygen curve for a mixture inwhich the percentage of oxygen is varied with variations of pressure insuch manner that there is always the same number of molecules of oxygenin each cubic centimeter as at sea-level condition of natural air. Thus,at sea-level pressure this curve passes through the point of (therebeing substantially 80% of inert gases in natural air, actually 79.01%)and there being substantially 20% oxygen in natural air (actually 20.99%The figures shown on the curve are, however, very close to theoretical.As the pressure is increased above the sea-level pressure, thepercentage of oxygen decreases, being the distance between the curve Cand the 100% line, so that, for example, at 3 atmospheres abovesea-level pressure the percentage of inert gas is shown as and that ofoxygen as 5%; or at 9 atmospheres above sea-level pressure, the percentinert is shown as 98% and the percent oxygen as 2%; but in all thesecases there will be the same number of molecules of oxygen per cubiccentimeter as at sea-level pressure, so that the breather will receiveat each breath the same full number of molecules of oxygen.

Conversely, the curve C has been carried backwardly from the line A topressures lower than sea-level pressures, such as exist in higheraltitudes. The curve C shows increasing percentages of oxygen for suchreduced pressures, with fall to 60% inert gases and 40% oxygen atone-half atmosphere absolute, and 0% inert gases and 100% oxygen at /5atmosphere absolute, corresponding to an elevation substantially 38,000feet above sea-level. That is to say, at /2 atmosphere a bsolute,corresponding to 17,000 feet above sea-level there should besubstantially 60% inert gases and 40% oxygen to provide a normal oxygencontent gas mixture; and at /5 atmosphere absolute, corresponding to38,000 feet above sea-level there should be a 100% oxygen content gasmixture; and at other intermediate pressures or elevations there shouldbe correspondingly proportioned gas mixtures, as shown by the curve C.With all such mixtures, the breather would receive a full supply ofoxygen at each breath, and thus should not experience discomfort due toshortage of oxygen. I therefore contemplate variations of the oxygencontent both above and below sea-level pressure operations; and thereducing valve units herein disclosed are capable of producing thedesired mixture of oxygen (or other gas) and inert (or other gas), undercontrolled conditions of operation of such units.

The curve B shows variation of percent of added inert gas when themixture comprises compressed natural air and other compressed inert gasadded thereto; both of such compressed gases being brought to the samecontrolled reduced pressure, and then mixed together under such equalityof pressures in the controlled ratio of such gases to each other. Thespace between the lines B and C represents the proportion of nitrogen,and the space below the line B represents the proportion of such addedinert gas, such as helium, when the mixture being produced comprises amixture of natural air and helium. Thus, for a pressure of 3 atmospheresabove sea-level pressure the inert components should comprise inertconstituents of the original natural air, and 75% compressed helium,being a total of 95% inert constituents; and there would remain 5%oxygen content, with the same number of molecules of oxygen per cubiccentimeter as at sea-level pressure. Or, at 9 atmospheres abovesea-level, the percent inert components of the original compressed airwould be 8%, and the percent added compressed helium, or other addedinert gas, would be 90%, being a total of 98% compressed inertconstituents.

The added inert gas in the examples given above may be helium, argon,krypton, xenon, or other gas suitable for the purposes of use to whichthe mixture is to be placed; but helium has been found to be desirablefor various reasons. Sometimes a combination of two or more such addedgases may be used. In any case the amount of the nitrogen, measured aspercent of the mixture, will thereby be lowered, with attendant benefitswell understood in the arts. In some cases all of the added inert gasmight be nitrogen, under the conditions of controlled reduced pressure(from the source of supply), and controlled ratio of the total inert gasto other component, such as oxygen.

In FIGURE 13 I have also shown, by the curves C and B the percentages ofoxygen and of added inert gas to obtain the desired constancy of oxygencontent, when the base pressure is assumed to be 1% atmospheres abovesea-level pressure, instead of sea-level pressure itself. In the case ofcurve C the percent oxygen has been constant at 80% up to the pressureof 1 A atmospheres above sealevel pressure; after which, for higherpressures such curve rises in proper form to establish or maintain thesame number of molecules of oxygen per cubic centimeter as are containedin a cubic centimeter of natural air at 1%. atmospheres above sea-levelpressure, the inert gases of the mixture including such proportions ofadded inert gas as are needed to conform to the requirements of thecurve. For example, at the pressure of 3 atmospheres above sea-levelpressure, the oxygen content would be about 12% (instead of 5% as in theprevious example); and the total inert gases would be 88% (instead of95% as in the previous example); and at a pressure of 9 atmospheresabove sea-level pressure, the oxygen content would be 4' /2% (instead of2% as .in the previous example), and the total inert gases would be 95/2% (instead of 98%, as in the previous example). Under theseconditions, too, the nitrogen content would fall from 80% at 1%atmospheres above sea-level pressure, to 18% at 9 atmospheres abovesea-level pressure.

In FIGURE 14 I have shown, more or less diagrammatically, the fact thatthe units of compressed gas absorbed by human blood and tissues, is lessin the case of helium or other inert gases, than the absorption ofnitrogen, and thus, that a greater degree of compression may be safelyused in such operations as deep-sea diving operations, than when all ofthe inert gas is nitrogen. The danger-line (corresponding tosubstantially 1% atmospheres above sea-level) is also shown on the chartof this figure.

The ability to provide the desired mixture of gases under exact controlof the ratios of such mixtures components, requires that both of thegases of such mixture shall be delivered to the mixing valve under closecontrol of both pressures and ratios, and that the connections from thereducing valves for the components, to the mixing chamber shall be ofthe same length, and very short. I have therefore provided a dual orduplex reducing valve and mixing valve arrangement complying with theabove stated requirements. The same is now described in detail asfollows.

Referring to FIGURES 1 to 12, inclusive, there are the two reducingvalves 25 and 26, and the mixing valve and chamber unit 27, immediatelyadjacent thereto. Each reducing valve includes the generally cylindricalchamber 28 of cup shape provided with the inner end flange 29. There isalso the intermediate cylindrical chamber 30', having the flanges 31 and32. At the inner ends of the chambers 28 of the two reducing valves arethe diaphragms 33 and 34, each including a thin flexible corrugatedplate or diaphragm 35, and the two rigid central plates 36 and 37 whichare secured to its central portion unyieldingly, but which allow thediaphragm as a Whole to flex easily. The peripheral portions of thesediaphragms and clamped firmly between the flanges 29 and the rings 38which are set against said peripheral portions and secured together.

The outer or cup portion of each of the chambers 28 is provided with arelatively large opening which is closed by a plug 39, preferably withthe intervening washer 40. Within each of the chambers 28 there issupported the high pressure chamber 41, having the three outwardlyprojecting arms 42, 43 and 44 by which it is supported in place; and theinner end of each of the high pressure chambers 41 is provided with thediaphragm 45 of sufficient flexibility to allow for flexing during theopening and closing operations of the valve, but of suflicient strengthto resist the high pressure gas within the chamber. The peripheralportion of each diaphragm 4 5 is secured to the inner end of the chamber41 by the ring 46.

The outer end of each of the high pressure chambers is provided with aremovable ring 4 screw threaded into place, and provided with theoutwardly extending circular ridge or seat 48, having a relatively sharpedge, and the sealing edge portion thereof is preferably ground tosecure a gas tight fit. The opening which receives the plug 39 alreadyreferred to is large enough to permit access to the ring 47, and otherparts, and removal thereof from time to time for replacement oradjustment through the unplugged opening.

There is a stem 49 which extends through the diaphragms 35 and 45, andis secured rigidly thereto by the set screws 50, 5 1, 52 and 53 (theportion 53 being shown for convenience as a flange on the stem itself).By these set screws the diaphragm-s are caused to operate with flexingmovement as a unit, also their movements are controlled.

Each stem 49 carries the valve member for the high pressure valve whichit controls. This is in the form of a slightly flexible disk 54 which isclamped between the set screws 55 and 56 of the stem, and the edgeportion of such slightly flexible disk carries the ring shaped seatingmember 57 in the form of a pair of rings clamped around the edge portionof the disk 54. The inner one of these rings serves to seat against theseat 48, and

for this purpose its inner face is preferably ground accurately. Also,the flexibility of the disk 54, while being sufficient to permitaccurate seating of the ring against the stationary seat, still isstrong enough to resist the internal pressure of the gas within thechamber 41, so that the seating and unseating of the ring are properlycontrolled by the stem 49.

The effective area of the disk 45 and the valve, to the line of contactwith the stationary seat, are equal to each other, so that the internalpressure within the chamber 41 is balanced, and only very slight forcesneed be exerted on the stem 49 to effect opening and closing movementsof the valve. It will, of course be understood that the stem itself issubjected to a large force between the positions of the disk 54 anddiaphragm 45, but this force is purely internal, and does not aflect theforce needed to effect the closing and unclosing movements of the valveas a whole. Due to the presence of the removable plug 39, the screws canbe reached for adjustment from time to time to bring the parts intoproper adjustment.

The plug 39 carries the outwardly extending set pin or stop 55* which isprovided with the set screw 56 by which it may be locked in adjustedposition. The clearance between the inner end of this set pin and thestem 49 is slight, being only a few hundredths of an inch, to permitfull opening and closing movements of the disk valve under limitedcontrol.

The arms 42, 4 3 and 44 which extend out from the high pressure chamber41 are carried by the screws 57*, 58 and 59, respectively. These arethreaded through the floors of recesses 60, 61 and 62 formed in the wallof the chamber 28, so that these screws may be reached from the outsideof the device for adjustment and change without having to completelydisassemble the device. Each of the screws 57 58 and 59 is threadedthrough both the floor of the chamber recess and the arm of the highpressure valve chamber; and in order to be able to secure adjustments ofthe arm positions by merely turning the screws, these screws areprovided with reverse threads on their two ends, so that turning thescrew serves to draw the arm towards the floor, or vice versa, dependingon the direction of such turn. Lock screws or nuts 63, 64 and 65 areprovided on the screws as shown.

There is a high pressure supply tube connected into each of the highpressure chambers 41, these being the tubes 66 and 6 7. They are passedthrough the chambers and 26 in gas tight manner, the details of whichneed not be disclosed, as any suitable form of such connection may beused.

The chambers 25 and 26 are provided with the delivery openings 68 and 69through which the low pressure gases are delivered to the mixing valveand chamber, presently to be explained. These openings are preferably ofrelatively large size due to the fact that the gas volumes which theyhandle are enlarged in proportion to the expansion taking place in thereducing valves. It will be understood, however, that these deliverypressures are equal, as will be presently explained. It is also notedthat due to the large crosssections of such passages, the lineal rate ofgas flow through them is reduced in proportion to that which would occurfor smaller cross-section passages. This benefits the objectivespreviously stated in this case, since thereby the production ofturbulence in the flowing gases is reduced.

It will be understood that in operation the high ressure gas enters thechamber 41 where it exerts pressure against the diaphragm 45 and againstthe valve member 5457. The areas of the diaphragm and of the valvemember are equal so that these pressures balance each other, andtherefore the opening and closing of the valve will be easily effected,and is controlled by external forces. Means are provided for exertingforce against the inner end of the stem 49, thereby tending to open thevalve, whereupon high pressure gas is permitted to flow into the chamber28 and connected parts and build up pressure therein. This pressure willbe exerted against the diaphragm 63-35, and tend to force the sameoutwardly, or into the central chamber 30, thereby seating the valve.Such seating of the valve will occur when the outward pressure of thediaphragm balances or slightly overcomes any unseating force against thestem 49.

It will be noted that the two reducing valves are so placed that theyact in opposition to each other, and that the seating movements of thetwo stems are towards each other, and that the unseating movements ofsaid stems are away from each other. Furthermore, by making the parts ofthe two reducing valves duplicates, it will be seen'that the deliverypressures at which they will act will be equal, so that the reducedpressures of the two gases will be equal.

Between the inner ends of the two stems 49, and within the chamber Iplace a control member and spring device for controlling the two valves,and also for ensuring balancing of the two valves against each other.

For this purpose there is secured a head block 70 to the inner end ofone stem 49, said head block carrying the two tapered rollers 71 and 72which are journalled radially in the head block. The inner end of theother stem 49 of the other reducing valve carries the head block 73which has the fiat and radially extending surface shown in FIGURE 7.There is another control block 74 located between the head blocks 70 and73, said control block 74 being provided with cam surfaces 75 and '76 inposition to receive the rollers 71 and 72 (see FIGURES 7, 9 and 10). Aball thrust bearing 77 is placed between the head block 73 and the backface of the control block, since these parts have relative movement. Itwill be understood that the stems 49 are held against rotation sincethey are securely locked to their diaphragms but they have slight backand forth movement.

When the two reducing valves are in operation, their stems 49 are forcedtowards each other, and thereby there is created a tendency to rotatethe control block to an initial position in which both of the reducingvalves are seated. By forcibly turning the control block the two stemswill be forced apart, thereby unseating one or both of the valves, andhigh pressure gas will be expanded into the two chambers 28, building uppressure therein, until finally the forces against the diaphragms 3336will be sufficient to cause the control block to rotate backwardlyagainst the force which turned it forwardly, and finally both of thevalves will be again seated.

There is a sleeve 78 journalled to the neck 79, which neck is carried bythe flange 80 in stationary manner. The sleeve 78 carries the outwardlyextending flange 81, and also carries the worm gear 82 by which theparts are controlled. There is placed a suitable spring between thecontrol member 74 and the flange 81, so that by turning the worm gearand flange 81, the spring will be placed under force or loaded, andthereby tend to force the control member 74 with a force depending onsuch spring loading. Thus the control member is placed under springforce of adjusted amount, and at the same time there is established ayieldable connection to the control member so that the same can yieldback and forth as one or both of the reducing valves functions.

There is a control shaft 82 extended through the chamber 30, so thatsaid shaft extends to the outside of the chamber at each side, butpasses close to the worm gear within the chamber. The worm 83 is mountedon said shaft within the chamber and in mesh with the worm gear. One endof the control shaft carriers the hand crank 84 by which the shaft isturned to adjust the device for pre-determination of the value of thereduced pressure of the delivered gases; or said shaft may be turned inany other convenient manner as will be presently explained.

It will be noted that the main moving parts of the device which aresubject to frictional contact are contained within the chamber 30, andalso that certain of these parts should be so placed that they can bereadily reached for adjustment from time to time. I have thereforeprovided the chamber 36 with the removable plate 85, which, whenremoved, gives access to the chamber through a large bottom opening,ample to permit ready access to those parts which may require adjustmentin the initial assembly of the device, or afterwards. Also, suitablelubricant may be placed within the chamber 30 to such amount as willeffectively lubricate the parts contained therein, thereby ensuring verysensitive operation of the cams, and other parts subject to movement. Inthis connection it may be noted that normally it is not necessary toprovide for more than a few hundredths of an inch movement of the valves54-57-in some cases not over a hundredth of an inch; and therefore theslight quivering or hunting back and forth motion of the control member74 as the valves are in use, will be only a few degrees of arc, the camsbeing of suitably steep taper. Thus a very sensitive device is produced,and one which will maintain the pressures of the delivered gases equaland constant to a very small degree of tolerance.

It is here noted that the back pressure on the diaphragms 3-5-37 opposesthe pressure existing within the chamber 28, and that the pressure whichmust be built up within said chamber 28 in order to seat the valve, isequal to the air pressure within the chamber 30 and against thediaphragm 35 plus the unseating force due to the pre-loading of thespring 115 of the control member. Therefore, in case of change of thepressure of the outside air (if the chamber 30 is in communication withthe outside air), as for example, when ascending to higher altitudes,the calibration of the device will be changed, with corresponding changeof the pressure above absolute zero at which the gases delivered by thereducing valves, will be delivered. In order to prevent such result andto ensure constant operation and constant delivery pressure aboveabsolute zero at various altitudes and various outside barometricreadings, I have provided means whereby the chamber 30 may be evacuated,thus ensuring a constant absolute zero back pressure within such chamber30. Under such conditions the operations will be solely effected by thepre-loading value of the spring. To produce such evacuation of thechamber 30, I have, in FIGURE 2 shown, more or less schematically, thesyphon unit 85 of conventional design and operation; and the aspiratingconnection of such syphoning unit 86, is connected by the tube 87 withone of the high pressure supply tubes 66 or 67, so that such syphoningunit will receive a constant supply of a small stream of high pressuregas, thus maintaining the desired vacuumized condition within thechamber 30. Conveniently such supply of high pressure gas may be derivedfrom the high pressure air side of the supplies. The connection 88 ofthe syphoning unit, being the suction side of such unit, is thenconnected by the tube 89 with the interior of the chamber 30 to maintainthe desired vacuum in such chamber. If desired a check valve 90 may beincluded in such tube 89, to prevent backflow of air therethrough, sincethe vacuum, once produced within the chamber 30, will only be broken byleakage into such chamber 30. Accordingly, it is usually unnecessary tomaintain the syphoning unit in continuous operation. Frequently thedevelopment of a vacuum within such chamber 30 will be unnecessary.However, when such vacuumized condition is produced and maintained inthe chamber 30, the need of re-calibration of the operation of the unitwill be avoided.

Instead of provision of the vacuumized condition within the chamber 30,for the purposes already stated, a spring 91 may be located behind thestem 49 at the location of each of the pressure reducing valves, orbehind each of the valve elements 54-57, each such spring beingcharacterized to exert the same pressure in the valve seating directionas the total force exerted on the corresponding diaphragm 3536 due tothe sea-level pressure on one side of such diaphragm, and zero or vacuumpressure on the other side thereof. In either case disclosed above (thesprings 91, characterized as above explained, or the vacuumizedcondition of the chamber 30), the control device spring 115 should be ofsuch characteristics as to just balance the seating force produced bysuch spring 91, or by vacuumized chamber 30, as a preloaded condition ofsuch spring 115. By thus pre-loading such spring 115, the zero point ofthe pressure scale will be that corresponding to zero absolute pressure,so that the delivered pressures of the pressure reduced gases will bereadily measurable on a scale of absolute pressure. This scale will beexplained hereinafter.

The gases delivered by the two reducing valves are to be broughttogether and mixed in pre-determined proportions. The construction forproducing this result will next be explained, as follows:

The two delivery ports 68 and 69 for the low-pressure (pressure-reduced)gases are connected to the two sides of a manifold 92, such connectionpreferably being made by means including the flexible connectors 93 and94. In the central portion of such manifold there is a semicircularpartial partition 95 having the large rectangular ports 96 and 97 whichgive access to the mixing chamber 98, also of semi-circular form. Thedelivery connection or pipe 99 leads from such chamber 98 for deliveryof the mixed gases under the pre-determined pressure, to the point ofconsumption or distribution.

Within the chamber 98 and directly behind the ports 96 and 97 there isplaced the quadrant shaped valve 100 which can be rocked back and forththrough approximately degrees of arc, being for this purpose mounted onthe vertical shaft 101. The valve normally stands in position to fullyclose one of the ports, for example 96, leaving the other port fullyopen; and as the valve is rocked from such defined position it graduallyopens the port 96 and simultaneously closes the port 97, so that therelative amounts of port openings are changed during such rock.Manifestly the incremental changes in the openings of the two ports willdepend on the forms of such ports, as well as the form of the valveitself. I have provided a semi-circular mask 102 placed between thepartial partition and the valve member 100. Such mask can be inserted orremoved conveniently by first removing the plate 103 from the bottomface of the manifold. This mask is shown, more or less diagrammaticallyand in development, in FIGURE 12 under the condition that the openingsand closings produced by the rock of the valve through successive equalincrements of rock, shall establish the ratios of gases called for bythe curve B of FIGURE 13. That is to say, the valve will commence withfull opening of the air port 97 for sea-level pressure and simultaneousfull closing of the valve 96 for Zero delivery of helium (or other gas);and as the ratio between the two gases is to be changed, the valve 97will close and the valve 96 will open, the incremental closings andopenings being such that, for equal increments of valve movement, theratios between the openings at any given position will correspond to theratios of air and helium (or other gas) which are to be delivered atvarious pressures, or for other reasons. It will be seen fromexamination of FIG URE 12 that a given movement of the shaded area(representing the member downwardly will uncover a given portion of theport 96 and due to the curved forms of the ports, these variations ofareas so covered and uncovered, will be according to the form of thecurve B. In case it is desired to provide any other form or manner ofvariation of the ratios of the port openings, such result may be securedby substitution of another mask having the properly formed portstherein.

The valve 100 is directly connected to the control shaft 82, such resultbeing secured by the worm gear 104 having the hub 105 which can besecured to the shaft 101 by means of the set screw 106, the controlshaft 82 carrying the worm 107 meshing with the worm gear 104. The valveshaft 101 is also provided with the knurled button 108 by means of whichit may be turned by hand to secure independent valve movement, in casesuch operation be desired, the set screw having first been released.

Conveniently there is placed a thin plate 109 on the knurled head orbutton 108, the same being provided with the markings 110 (see FIGURE 2)to indicate valve openings or ratios for which purpose the pointer 111is also provided with the dial 112 connected to the control shaft 82 bythe worm gear and worm connections 113-114, so that this dial will turnwith the control shaft movements, and therefore according to thechanging delivery-reduced-pressure of the gases. Due to the fact thatboth of the dials 110 and 112 are moved by the control shaft, it isnecessary to bring them into proper coordination. Accordingly, I haveprovided the set screw 106 already referred to, whereby this result maybe produced. It may also be necessary or desirable to substitute otherdials from time to time, as for example, when the mask is changed. Suchsubstitutions may also be readily made, with replacement of the plate109 by another plate carrying proper markings, and properly calibrated.

The spring unit 115 (see FIGURE 7) of the control element preferablycomprises three coiled spring elements, all coiling in the samedirection, and the middle one being of double the strength of each ofthe two outside ones. The ends of such middle spring element areconnected to the control member and to the flange 81 at positions 180degrees from the positions of connection of the ends of the two outsidespring elements. Thus the radial components of force developed by theloadings of the spring elements will balance each other, with avoidanceof lateral friction components against the bearings, and which wouldotherwise be generated due to such radial components of force; it beingalso understood that in the case of pressure reductions by large sizedunits the spring elements will probably be of considerable length.

It will be understood that the delivery opening from the ratiodetermining valve, such opening being defined by the flange 99 (FIGURES2, 3, 4, 5, 6 and 7), connects to whatever conduit is intended toreceive the gas mixture. Therefore the pressure of the delivered gasflowing through such flanged opening will be that reduced pressure forwhich the unit is set and is operating. Such pressure, although areduced pressure, may nevertheless be considerable, especially when themixture is being delivered to a caisson or to a deep-sea diver operatingat considerable depth below the water surface. Nevertheless, it may, insome cases, be desirable to produce a slight back pressure against themixed gases directly after they leave the proportioning valve, to betterensure intimate mixing of the components. Accordingly, I have, inseveral of the figures shown the wing valve including the wings 184 and185 in the delivery flange connection, the same being pivoted on theshafts 186 and 187, respectively, so that such wings swing towards andfrom each other to provide an opening between them more or lessaccording to the volume of the mixture then being demanded. Lightsprings 188 and 189 are provided on these shafts 186 and 187, urging thewings to rock in the closing direction. Such springs will thus serve toproduce a differential of pressure or pressure drop as the gas mixturepasses between the wings, such differential usually being a minor matterin comparison to the absolute pressure (reduced) at which the mixture isfinally delivered to its point of consumption or use.

It is noted that both the adjusted position of the spring unit 115 andthe rotated position of the valve element 100are related to each otherby the common adjusting shaft 82 Due to this relation, when used, therelative proportions of the two gaseous components are directly relatedto the delivered pressure of the gases. This relationship is consonantwith the requirements imposed by the relationship between gasproportions and pressures as defined, for example by the curves ofFIGURES 13 and 14. Since the relation between the proportions of the twogaseous components is produced by the form of the openings in the maskplate of the dual valve, it follows that any specified relation of suchproportions of the two gases, varying according to some variable of thegas pressures, may be obtained by substitution of the mask having itsopenings formed to meet the defined specifications.

It has also been stated that the adjustment of the spring produced byuse of the hand crank 84 may, if desired be produced by rotation of theshaft 82 by other means, such as by connection of such shaft with theequipment carried by the diver, to rotate such shaft according to thedescents or raisings of the diver during his operations. It is notedthat such shaft 82 is shown in FIGURE 8 as being broken away at itslower end (proximate to the viewer of such figure). Accordingly, suchshaft may be connected to some element of the structure to which thegaseous mixture is being delivered, for automatic control of thefunctions of the pressure reducing and proportion controlling unit, forsuch automatic control of the delivered pressure and the deliveredproportionof the gaseous components to each other, as may be requiredfrom time to time, by such structure to which the mixture is beingdelivered.

I claim:

1. A multiple balanced pressure-reducing and delivering andproportion-controlling valve unit; comprising in combination a pair ofpressure reducing valve units, each including a reduced-pressuregas-receiving chamber, and a control valve opening into such chamber,and including adjustable delivered-reduced-pressure regulating means,together with a common delivered-reduced-pressure control unit betweenthe delivered-pressure, reduced-pressure regulating means of the twovalve units; said control unit being constituted to cause each of thepressure reducing valve units to deliver gas into its gas-receivingchamber at the same reduced pressure as the other pressure reducingvalve unit; together with a gas reduced-pressure receiving manifold inproximity to both of the valve units, and having its end portions incommunication with the proximate chambers; together with a commondelivered gas proportioning valve element located in the central portionof the manifold, and dividing the manifold into separated portionscommunicating with the respective reduced-pressure gas-receivingchambers; wherein said proportioning valve includes a mixed gas deliveryopening in the manifold at the location of the proportioning valveelement; and wherein said proportioning valve includes a circulararcuate partition extending across the central portion of the manifoldand having its end portions connected to the manifold wall at the sidesof said mixed gas de livery opening, a segmental arcuate movable valveelement journalled for rotary movement about an axis coaxial with thepartition, an arcuate mask plate between the proximate opposing surfacesof the partition end of the valve unit; together with means constitutedto rock the movable valve element about its axis, to selected angularpositions.

2. A valve structure as defined in claim 1; wherein the commondelivered-reduced-pressure control unit is adjustable in mannerconstituted to cause the delivered gas to be delivered into thereduced-pressure gas-receiving chamber of each valve unit at the samereduced pressure as is delivered by the other valve unit; together withmeans to adjust said control unit for delivery of gas by each valve unitat a pre-selected pressure.

3. A valve structure as defined in claim 2; together with common meansto adjust said pressure control unit to the pre-selected pressure, andto simultaneously cause the movable valve unit of the proportioningvalve to be in moved position corresponding to a pre-determined relationbetween the reduced pressure of the gases and the the proportions ofsuch gases delivered through the proportioning valve, to each other.

4. A valve structure as defined in claim 3; wherein the 'pre-determinedrelation between the reduced pressure of the gases and the proportionsof such gases delivered through the proportioning valve, to each other,varies according to a predetermined proportion for different reducedgas-pressure values and wherein the control unit and the proportioningvalve, and said common means to adjust the control unit and to cause themovable proportioning valve unit to be in moved position correspondingto a pre-determined relation between the reduced pressure of the gasesand the proportions of such gases to each other, is constituted to causethe pressure control unit, and the movable proportioning valve unit, tobe in successively moved positions related to each other at each suchposition, to correspond to the pre-determined relation between thereduced pressure of the gases and the 1 3 proportions of such gases toeach other, for each such moved position of said parts.

5. A valve structure as defined in claim 4; wherein the gases compriseoxygen and an inert gas suitable for intake into the human breathingsystem; wherein the predetermined relation between the reduced pressureof the gases and the proportions of such gases to each other, comprisesa pre-determined proportion of the oxygen and such inert gas,pre-determined according to the reduced pressure of the mixture of suchoxygen and such inert gas.

6. A valve structure as defined in claim 5; wherein the inert gascomprises helium.

7. A valve structure as defined in claim 5; wherein the inert gascomprises helium and nitrogen.

References Cited by the Examiner UNITED STATES PATENTS 1,780,589 11/1930Hendrix 137-99 2,330,151 9/1943 Smith 137612 X 2,725,067 11/1955 Howell137612 2,986,152 5/1961 Boyer 13799 WILLIAM F. ODEA, Primary Examiner.

CLARENCE R. GORDON, Examiner.

1. A MULTIPLE BALANCED PRESSURE-REDUCING AND DELIVERING ANDPROPORTION-CONTROLLING VALVE UNIT; COMPRISING IN COMBINATION A PAIR OFPRESSURE REDUCING VALVE UNITS, EACH INCLUDING A REDUCED-PRESSUREGAS-RECEIVING CHAMBER, AND A CONTROL VALVE OPENING INTO SUCH CHAMBER,AND INCLUDING ADJUSTABLE DELIVERED-REDUCED-PRESSURE REGULATING MEANS,TOGETHER WITH A COMMON DELIVERED-REDUCED-PRESSURE CONTROL UNIT BETWEENTHE DELIVERED-PRESSURE, REDUCED-PRESSURE REGULATING MEANS OF THE TWOVALVE UNITS; SAID CONTROL UNIT BEING CONSTITUTED TO CAUSE EACH OF THEPRESSURE REDUCING VALVE UNITS TO DELIVER GAS INTO ITS GAS-RECEIVINGCHAMBER AT THE SAME REDUCED PRESSURE AS THE OTHER PRESSURE REDUCINGVALVE UNIT; TOGETHER WITH A GAS REDUCED-PRESSURE RECEIVING MANIFOLD INPROXIMITY TO BOTH OF THE VALVE UNITS, AND HAVING ITS END PORTIONS INCOMMUNICATION WITH THE PROXIMATE CHAMBERS; TOGETHER WITH A COMMONDELIVERED GAS PROPORTIONING VALVE ELEMENT LOCATED IN THE CENTRAL PORTIONOF THE MANIFOLD, AND DIVIDING THE MANIFOLD INTO SEPARATED PORTIONSCOMMUNICATING WITH THE RESPECTIVE REDUCED-PRESSURE GAS-RECEIVINGCHAMBERS; WHEREIN SAID PROPORTIONING VALVE INCLUDES A MIXED GAS DELIVERYOPENING IN THE MANIFOLD AT THE LOCATION OF THE PROPORTIONING VALVEELEMENT; AND WHEREIN SAID PROPORTIONING VALVE INCLUDES A CIRCULARARCUATE PARTITION EXTENDING ACROSS THE CENTRAL PORTION OF THE MANIFOLDAND HAVING ITS END PORTIONS CONNECTED TO THE MANIFOLD WALL AT THE SIDESOF SAID MIXED GAS DELIVERY OPENING, A SEGMENTAL ARCUATE MOVABLE VALVEELEMENT JOURNALLED FOR ROTARY MOVEMENT ABOUT AN AXIS COAXAL WITH THEPARTITION, AN ARCUATE MASK PLATE BETWEEN THE PROXIMATE OPPOSING SURFACESOF THE PARTITION END OF THE VALVE UNIT; TOGETHER WITH MEANS CONSTITUTEDTO ROCK THE MOVABLE VALVE ELEMENT ABOUT ITS AXIS, TO SELECTED ANGULARPOSITIONS.